Heater for drums



y 5, 1965 E. P. MGGINN 3,185,145

HEATER FOR DRUMS Filed Aug. 1, 1962 H62 3 o u 11 2 6 3 I Y I /5 I [H EAR L P i l l Z NN M i'M ATTORNEYS United States Patent 3,185,145 HEATER FOR DRUMS Earl P. McGinn., Verona, N.J., assignor to Drew Chemical Corporation, a corporation of Delaware Filed Aug. 1, 1962, Ser. No. 213,965 5 Claims. (Cl. 126-369) The present invention is directed to a heater for various purposes, and more particularly for the heating of drums or the like containing liquid or fusible solids.

Many heating devices for such general purpose have been known and used. Among them is a furnace Within which a drum may be held and a flame of gas or oil projected into the furnace to heat the contents of the drum. However, such a device is disadvantageous in that it is difiicult to so control the amount of heat introduced into the drum so as to uniformly heat the contents Without local overheating. To overcome this, it has been proposed to provide indirect heating, for instance by a water bath, but the transfer of heat from a water bath is too slow for most commercial purposes. A further attempt to speed up the heating consisted in providing a steam jacket about a drum, which was capable of heating the contents more uniformly and at a higher rate than a water bath. However, the penetration of heat through the material being heated is relatively slow so that such a system of heating was not entirely satisfactory.

The present invention is intended and adapted to overcome the difiiculties and disadvantages inherent in devices of the type described, it being among the objects of the present invention to provide a self-contained heating unit or device, with which a drum or the like to be heated may be associated, and wherein a heated drum may be readily replaced by a drum to be heated.

It is also among the objects of the present invention to provide a heating device which will supply heat by direct contact to the drum by conduction, and also to supply heat indirectly whereby convection currents are set up to provide a uniform heating of the contents of a drum or the like.

It is still further among the objects of the present invention to provide a device of the type described, which is quite simple in construction, is inexpensive, is highly eflicient in operation and which utilizes both steam and direct heat for the heating of said drum or the like.

In practicing the present invention, there is provided a container, preferably of cylindrical shape, having a diameter which is large relative to the depth thereof. The container is closed but has an inlet for steam and an outlet for condensate, arranged preferably on the side wall of the container.

It is important to the present invention that the top of the container be provided with a series of holes along the central area, the diameter of the holes being quite small relative to the diameter of the container. Such holes are in the central portion of the top of the container, the outer portions thereof being imperforate. It is also important that the top have a convex form.

The invention is more fully described in connection with the accompanying drawing, in which like reference characters indicate like parts, and in which:

FIG. 1 is a top plan view of a heating device made in accordance with the present invention, and

3,185,145 Patented May 25, 1965 "ice FIG. 2 is a transverse cross-sectional view thereof taken along line 2-2 of FIG. 1.

The heater 1 consists essentially of a bottom plate 2 and a convex top plate 3, which are joined as by welding, to circular wall 4 thereof. The bottom edge 5 of wall 4 extends a substantial amount-below bottom 2 of the container. Said bottom slopes from point 6 to point 7, which is substantially at the lower edge of drain pipe 8. A feed pipe 9 for live steam is provided, as shown particularly in FIG. 1.

In top or cover 3 of container 1 and at the vertical axis 10 thereof, is a hole 10'. Surrounding said hole and at a distance therefrom, usually equal to about one-fourth of the radius of the drum, is a series of holes 11 constituting an inner circle. A second series of holes 12 constituting an outer circle, are arranged on a radius of about one-half the radius of container 1. Usually holes 11 are spaced at about 60 apart and holes 12 are usually spaced at about 30 apart. All of the holes are of ap proximately the same diameter and are quite small relative to the diameter of the drum, being less than about one-sixtieth thereof. They may also be as small as oneninetieth of said diameter.

Various sizes of heaters may be made in accordance with the invention but it is desirable that the relative dimensions thereof be approximately the same. A specific example of the invention is a case where container 1 is about 22 inches in diameter, holes 10, 11 and 12 are about one-fourth inch in diameter, and inlet and outlet 8 and 9 about one-half inch in diameter. The thickness of the metal constituting walls 4, top 3 and bottom 2, are about one-fourth inch. The height of the wall is about three inches and the apex of. top 3 is about one-half inch higher than the edges of said top.

In the use of the heating arrangement, a drum of material, the bottom of which may be convex or concave, is placed upon top 3. If it is convex, the weight of the material therein will cause the bottom of the drum to become concave and to make close contact with top 3. Steam is introduced through inlet 9 and heats top 3, causing conduction of heat through the bottom of the drum and into the material therein. As the steam pressure builds up, steam passes outwardly through holes 10, 11 and 12, forming a thin film of steam which radiates outwardly and gives up most of the heat of condensation in the central portion of the drum, heating the material therein, which rises and causes convection currents to flow upwardly along the center and downwardly along the periphery of the drum. As the steam passes outwardly to the imperforate part 13 of the drum, it is condensed to water, which flows outwardly beyond the container.

The principal advantage of this heater is its simplicity and low cost, as well as the speed with which it supplies heat to the bottom of a steel drum. The drum sits on top of the heater so that the two metal surfaces are in intimate contact, thus allowing rapid heat transfer by conduction through the metal. In addition, when the steam pressure is sufiiciently high, there will be some movement of steam through the holes of the heater plate directly to the bottom surface of the drum. This allows a much greater heat transfer than by conduction through the metal.

The use of this heater also produces convection cur rent in the material inside the drum, thus producing mix- 3 ing of the contents. In practice, applicant has been able to obtain a rise of 40 F. for the entire contents of a 55 gallon drum in thirty minutes.

What is claimed is:

1. A heating means for drums and the like comprising a closed container for heated fluid having an upstanding continuous side wall, an upwardly convexed top plate, and a sloped bottom plate disposed within said side Wall and above the lower edge thereof, means for introducing heated fluid into said container, means for removing fluid from said container at the lowermost portion of said bottom plate, a series of relatively small holes in the central part only of said top plate, said holes being in a plurality of concentric circles and the radius of said top plate being about twice the radius of the outermost circle of holes, said container being adapted to heat a drum placed on said top plate with said drum covering said holes, extend-v ing beyond the outermost holes and being in metal to metal contact with said top plate.

2. Heating means according to claim 1 characterized in that said holes are arranged in at least two concentric circles and a single hole is in the center of said circles.

3. Heating means according to claim 1 characterized in that the diameter of said holes is less than one-sixtieth of the diameter of said drum.

4. Heating means according to claim 1 characterized in that the holes of the inner circle are spaced about 60 apart.

5. Heating means according to claim 1 characterized in that the holes of the outer circle are spaced about 30 apart.

References Cited by the Examiner UNITED STATES PATENTS 177,151 5/76 Peace et al 126-369 225,317 3/ 80 Ashcroft 12633 337,303 3/86 Burkhard 12633 780,851 1/05 Wilson 1263 69 843,698 2/07 Redwood 126369 1,086,940 2/ 14 Ryon 12620 X 1,109,828 9/14 Goff 126-377 1,174,994 3/16 Klepach 126-33 1,203,322 10/16 Freeman 126--3 69 1,453,378 5/ 23 Clifford 126-377 2,963,957 12/60 Tashrnan 1263 69 X FOREIGN PATENTS 559,302 9/ 32 Germany.

JAMES W. WESTHAVER, Primary Examiner.

PERCY L. PATRICK, Examiner. 

1. A HEATING MEANS FOR DRUMS AND THE LIKE COMPRISING A CLOSED CONTAINER FOR HEATED FLUID HAVING AN UPSTANDING CONTINUOUS SIDE WALL, AN UPWARDLY CONVEXED TOP PLATE, AND A SLOPED BOTTOM PLATE DISPOSED WITHIN SAID SIDE WALL AND ABOVE THE LOWER EDGE THEREOF, MEANS FOR INTRODUCING HEATED FLUID INTO SAID CONTAINER, MEANS FOR REMOVING FLUID FROM SAID CONTAINER AT THE LOWERMOST PORTION OF SAID BOTTOM PLATE, A SERIES OF RELATIVELY SMALL HOLES IN THE CENTRAL PART ONLY ON SAID TOP PLATE, SAID HOLES BEING IN A PLURALITY OF CONCENTRIC CIRCLES AND THE RADIUS OF SAID TOP PLATES BEING ABOUT TWICE THE RADIUS OF THE OUTERMOST CIRCLE OF HOLES, SAID CONTAINER BEING ADAPTED TO HEAT A DRUM PLACED ON SAID TOP PLATE WITH SAID DRUM COVERING SAID HOLES, EXTENDING BEYOND THE OUTER MOST HOLES AND BEING IN METAL TO METAL CONTACT WITH SAID TOP PLATE. 